Anti-starvation and bounce-reduction mechanism for a two-dimensional bufferless interconnect

摘要

A slot reservation method is disclosed. The slot reservation method generates slot reservations in two dimensions to address starvation and to reduce bounce of messages transmitted through an interconnect. An interconnect implemented using the slot reservation method is capable of being scaled to larger network-on-chip implementations.

主权项

1. An apparatus comprising:
a plurality of agents disposed on an interconnect, the interconnect comprising at least one horizontal ring and at least one vertical ring, the agents to communicate using flits, wherein flits, short for flow control digits, are the smallest unit of flow control on the interconnect; a buffer to store a plurality of flits on behalf of a first agent, the plurality of flits to be transmitted to a second agent on the interconnect; a plurality of ring slots disposed upon both the horizontal ring and the vertical ring, where a ring slot is associated with each agent of the plurality of agents; a software program to place a slot reservation in one of the rings in response to a counter reaching a threshold value, the software program to further set n bits in a register with a value corresponding to the first agent, where integer, n, corresponds to 2n agents located on the interconnect; a horizontal ring stop to process flits received from the agent intended for the second agent on the interconnect; and a vertical ring stop to process flits received from the horizontal ring, wherein flits processed by the vertical ring stop are sent to the second agent by way of the vertical ring.